Received-SPF: pass (google.com: domain of linux-kernel+bounces-23610-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249;
Message-ID: <ed4db18f-5590-40a6-adbe-53062d0f382b@linux.intel.com>
Date: Thu, 11 Jan 2024 15:01:48 +0200
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: i2c-designware: NULL ptr at RIP: 0010:regmap_read+0x12/0x70
To: Kim Phillips <kim.phillips@amd.com>, "V, Narasimhan"
 <Narasimhan.V@amd.com>, Borislav Petkov <bp@alien8.de>,
 "linux-i2c@vger.kernel.org" <linux-i2c@vger.kernel.org>
Cc: lkml <linux-kernel@vger.kernel.org>,
 Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
 Mika Westerberg <mika.westerberg@linux.intel.com>,
 Jan Dabros <jsd@semihalf.com>, Andi Shyti <andi.shyti@kernel.org>,
 "Limonciello, Mario" <Mario.Limonciello@amd.com>
References: <20231229120820.GCZY62tM7z4v2XmOAZ@fat_crate.local>
 <8169d773-f9ec-4092-b036-9e4fd59966c3@linux.intel.com>
 <DM4PR12MB508654DF49FE079D6C283D658961A@DM4PR12MB5086.namprd12.prod.outlook.com>
 <888da30a-c1ed-4fb0-af81-787fd868ce20@linux.intel.com>
 <DM4PR12MB5086DE2882C7C5044697B1C38967A@DM4PR12MB5086.namprd12.prod.outlook.com>
 <adf6c24a-d94b-40e5-b645-0c6b23b2d513@linux.intel.com>
 <DM4PR12MB508652E9A422CF639C2FEEC0896A2@DM4PR12MB5086.namprd12.prod.outlook.com>
 <e059928c-6fab-4ca2-9615-4401ee16fb82@linux.intel.com>
 <27cf56b5-d21b-4906-823f-a9e567fc26e2@amd.com>
Content-Language: en-US
From: Jarkko Nikula <jarkko.nikula@linux.intel.com>
In-Reply-To: <27cf56b5-d21b-4906-823f-a9e567fc26e2@amd.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit

Hi

On 1/11/24 00:56, Kim Phillips wrote:
> Hi,
> 
> On 1/9/24 4:11 AM, Jarkko Nikula wrote> On 1/9/24 09:56, V, Narasimhan 
> wrote:
>>>   * Looks like the issue is with this below commit:
>>>   * i2c: designware: Fix lock probe call order in dw_i2c_plat_probe()
>>>
>> Hmm... This makes me even more confused since your device AMDI0010 
>> should not even use the access semaphore.
>>
>> So linux-next works if you run a commit before it or revert these 
>> three patches? (commit 2f571a725434 ("i2c: designware: Fix lock probe 
>> call order in dw_i2c_plat_probe()") doesn't revert without reverting 
>> two other related commits after it)
>>
>> git show f9b51f600217b38f46ea39d6aa445e594bf3eb30 |patch -p1 -R
>> git show b8034c7d28a988be82efbf4d65faa847334811f7 |patch -p1 -R
>> git show 2f571a72543463ef07dc3ac61e7b703b9ad997f9 |patch -p1 -R
> 
> Narasimhan is right, if I check out, build and boot this commit:
> 
>        2f571a725434 i2c: designware: Fix lock probe call order in 
> dw_i2c_plat_probe()
> 
> I get the same stacktrace on the serial console.
> 
> If I try the previous commit (174a0c565cea "efi/loongarch: Directly 
> position the loaded image file"),
> the system boots fine.
> 
> The same thing happens with the three reversions above:
> next-20240110 gets the stacktrace, but with the three
> reversions, it doesn't.
> 
Thanks, I just sent a fix reverting those commits.

> Is your parallel post probe runtime suspending time window
> theory no longer applicable?  These AMD EPYC systems have a
> lot more cores than their client equivalents, and AMD power
> management code has had a lot of improvements lately.
> 
It still a mystery to me but I let Andy to figure out it if he wants to 
during next development cycle :-)